1. Field of the Invention
The present invention relates to an image forming apparatus for image formation such as image recording in response to an original image or to image information entered from an exterior apparatus.
2. Description of the Prior Art
In conventional apparatus capable of image recording according to different image sources, the recording condition or the recording operation is controlled in different manners according to the image source to be recorded. Also, when an image recording is requested from another source during the image recording operation by scanning an original and such other image recording is given priority, the original scanning is repeated afterwards to complete the image recording operation. During the image recording operation of an image supplied from an outside apparatus, the image recording by original scanning cannot be conducted and access to the apparatus is prohibited until the completion of the recording operation under way.
Also, in a case of synthesized recording, for example, of an original image and data recorded on a magnetic tape or the like, there have been required various signal exchanges and detailed control procedures for recording line registration and signal synchronization.
Also, in an apparatus having such synthesized recording mode, once the recording operation in the synthesized recording mode is commenced, a recording operation without such synthesis can only be initiated by interrupting the recording in the synthesis mode and selecting anew a desired recording mode.
Furthermore, there is already known a local area network for image recording through image transmission among stations equipped with image reading devices and image recording devices. In such a network, the image reading device and the image recording device in each station may be directly connected for achieving a local copying mode for making a copy in the same manner as in the conventional copier.
In such a system, the priority of the recording operation for the transmitted image and of the local copying is determined by the state of utilization and the condition of installation of each station. Such priority is important in relation to the process for a demand for interruption during a recording operation.
Furthermore, in such apparatus, there is proposed, in case of a demand for recording another image during the image recording operation for transmitted information, to permit the demand according to the necessity. In such recording mode, however, the preceding recording mode may be forgotten, for example, if the interruption is extended in time.
Furthermore, the case when an erroneous stop instruction is given to an apparatus capable of accepting a demand for interruption, it is preferable that the mode before stop can be immediately restored for achieving smooth information processing. Furthermore, in such apparatus, the function is usually completely stopped in response to an abnormal situation, so that certain procedures are needed in order to restart the recording operation.
Furthermore, in such an image forming apparatus, signal exchange is conducted, for example, for each line in order to synchronize the image recording device with the image information generating device, so that the latter is required to have a program exclusive for a printing operation, an interface, etc. Also in case of information recording with a size modification, there are required a data processing circuit and a complicated program for such image size modification. Such circuit and software are required also for image trimming.
Furthermore, in the conventional copier, copying of a desired image only of an original is achieved by suitable work on the original, such as cutting out the desired image area or covering the unnecessary area. Such work is however tedious, and may smear or destroy the original.
Furthermore, in a case of recording image information supplied from an outside device on a recording sheet, a permission signal for sheet feeding is given to the outside device according to the working state of the recording device, and, in response to the signal, the outside device dtermines the timing of sheet feeding for each sheet feeding. Consequently the signal exchange for sheet feeding has to be conducted between the recording device and the outside device, thus requiring a complicated control procedure.
Furthermore, in a case of synthesizing plural information for recording, the number of recordings of such synthesized information is to be determined by a predetermined information source, and the information output of plural information sources is controlled according to the thus determined number. Consequently, a device lacking the ability to determine the number may not be able to obtain the recordings of the determined number. Also inconvenience may arise if the desired number differs between the information sources.
Furthermore, in a recording apparatus for recording information supplied from an outside device, the recording operation is controlled by control signals, such as a sheet feeding signal, supplied from the outside device. The quantity of information, namely the number of recordings, supplied form the outside device cannot be known at the recording device.
When the outside device is a computer or the like, the quantity of recordings tends to become very large, thus requiring a display device of a large number of digits, giving rise to an increased manufacturing cost and an increased space for installation.
Furthermore, in an apparatus capable of a local copying mode for copying an image supplied from an image output device combined with the recording device, the operator is unable to know the quantity of interruption recordings requested from an outside device.